Mozilla Foundation Security Advisory 2008-41

Privilege escalation via XPCnativeWrapper pollution

Announced

September 23, 2008

Reporter

moz_bug_r_a4, Olli Pettay

Impact

Critical

Products

Firefox, SeaMonkey, Thunderbird

Fixed in

Firefox 2.0.0.17

Firefox 3.0.2

SeaMonkey 1.1.12

Thunderbird 2.0.0.17

Description

Mozilla security researcher moz_bug_r_a4 reported a
series of vulnerabilities by which page content can pollute
XPCNativeWrappers and have arbitrary code run with chrome privileges.
One variant reported by moz_bug_r_a4 only affected Firefox 2.

Mozilla developer Olli Pettay reported that XSLT can
create documents which do not have script handling objects. moz_bug_r_a4
also reported that document.loadBindingDocument() returns a
document that does not have a script handling object. These issues could
also be used by an attacker to run arbitrary script with chrome privileges.

Thunderbird shares the browser engine with Firefox and
could be vulnerable if JavaScript were to be enabled in mail. This is not
the default setting and we strongly discourage users from running
JavaScript in mail.

Workaround

Disable JavaScript until a version containing these fixes can be installed.